Automatic Headlights Using DEI 545t NiteLite Won't Turn OFf

I just bought a base model 2007 Prius, and wanted to add a few things to the sparse features. While I was upgrading the stereo, I decided to install automatic headlights as well, using the DEI 545t NiteLite kit. I've got everything in, and double-checked wiring (the two power leads are hooked up to the stereo's similar leads, and the two relay grounds and control unit grounds are attached bolts on the metal panel in front of the fuse box).

The lights now come on on their own. The problem is, the lights won't go off as long as the ignition is on: even in bright sunlight, even if I flip the included switch, I get headlights on. Has anyone ever seen anything like this before?

 

OK, I think I've found my answer: I tried to wire the 545t for the wiper control, and the wire I used was an input to the wiper switch, meaning it's always on (when the ignition is on) once it's been tapped and thereby grounded. The result is the 545t always thinks the wiper is on, and runs the headlights constantly--and the 545t's off switch doesn't work, because that only turns off the photovoltaic switch.

The wire I tapped was one identified in the Gen III forums, but given that the Gen II connector looks identical to the Gen III connector, I'm not sure it'll work on either. As it turns out, I'm not sure of the best way to wire it, because the wiper motor has two separate circuits for low/intermittent/wash and high. I'll start a new thread with the details, because I think people will be interested in it for reference purposes.